How to display the contents of a file in unix
there are many ways to view the contents of a file =commands= *cat command: print all the contents of the file in terminal. If the contents of your file is larger than a page, cat will not stop paging through the program until it hits the end :Hint: shift-page up and shift-page down allow you to page up and down in you terminal, so you can view previous output *more: prints the contents of a file. If the file is more than a page, it waits and allows you to scroll down the page with the down arrow key. It does not let you go up in the file *less: is like more but allows you to go up and down in the file. It also uses page up and page down, and many other functions like searching. See: Howto use the less command =Commands for displaying parts of files= *head: displays the first 10(default) lines of a file :-c, --bytes=-N ::print the first N bytes of each file; with the leading `-',print all but the last N bytes of each file :-n, --lines=-N ::print the first N lines instead of the first 10; with the leading `-', print all but the last N lines of each file :-q, --quiet, --silent ::never print headers giving file names :-v, --verbose ::always print headers giving file names *tail: similar to head except prints the last 10(default) lines of a file. :--retry ::keep trying to open a file even if it is inaccessible when tail starts or if it becomes inaccessible later -- useful only with -f :-c, --bytes=N ::output the last N bytes :-f, --followdescriptor} output appended data as the file grows; ::-f, --follow, and --follow=descriptor are equivalent :-n, --lines=N ::output the last N lines, instead of the last 10 :--max-unchanged-stats=N ::with --follow=name, reopen a FILE which has not changed size after N (default 5) iterations to see if it has been unlinked or renamed (this is the usual case of rotated log files) :--pid=PID ::with -f, terminate after process ID, PID dies :-q, --quiet, --silent ::never output headers giving file names :-s, --sleep-interval=S ::with -f, each iteration lasts approximately S (default 1) seconds :-v, --verbose ::always output headers giving file names :--help display this help and exit :--version ::output version information and exit *grep: displays all lines that match a specified phrase :Usage: grep phrase filename :See: Howto use the grep command *sed : sed is very complex. :See: Howto use the sed command *gawk : gawk is very complex. :See: Howto use the gawk command =pipes= * cat filename|head : same as head filename * cat filename|tail : same as head filename * cat filename|more : same as more filename * cat filename|grep phrase : same as head phrase filename * cat filename|head|grep phrase : prints the first 10 line that have if they have phrase in them : same as head filename|grep phrase * cat filename|grep phrase|head : prints the first 10 line that have phrase in them : same as grep phrase filename|head =See Also= *Guide to unix text editors From HowTo Wiki, a Wikia wiki. Category:Howto